Skip to main content

Digital Backpropagation in the Nonlinear Fourier Domain

Author(s): Wahls, Sander; Le, Son T; Prilepsky, Jaroslaw E; Poor, H Vincent; Turitsyn, Sergei K

To refer to this page use:
Abstract: Nonlinear and dispersive transmission impairments in coherent fiber-optic communication systems are often compensated by reverting the nonlinear Schrödinger equation, which describes the evolution of the signal in the link, numerically. This technique is known as digital backpropagation. Typical digital backpropagation algorithms are based on split-step Fourier methods in which the signal has to be discretized in time and space. The need to discretize in both time and space however makes the real-time implementation of digital backpropagation a challenging problem. In this paper, a new fast algorithm for digital backpropagation based on nonlinear Fourier transforms is presented. Aiming at a proof of concept, the main emphasis will be put on fibers with normal dispersion in order to avoid the issue of solitonic components in the signal. However, it is demonstrated that the algorithm also works for anomalous dispersion if the signal power is low enough. Since the spatial evolution of a signal governed by the nonlinear Schrödinger equation can be reverted analytically in the nonlinear Fourier domain through simple phase-shifts, there is no need to discretize the spatial domain. The proposed algorithm requires only O(D log 2 D) floating point operations to backpropagate a signal given by D samples, independently of the fiber's length, and is therefore highly promising for real-time implementations. The merits of this new approach are illustrated through numerical simulations.
Publication Date: 2015
Citation: Wahls, Sander, Son T. Le, Jaroslaw E. Prilepsk, H. Vincent Poor, and Sergei K. Turitsyn. "Digital backpropagation in the nonlinear Fourier domain." In 2015 IEEE 16th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), (2015): 445-449. doi:10.1109/SPAWC.2015.7227077
DOI: doi:10.1109/SPAWC.2015.7227077
ISSN: 1948-3244
EISSN: 1948-3252
Pages: 445-449
Type of Material: Conference Article
Journal/Proceeding Title: 2015 IEEE 16th International Workshop on Signal Processing Advances in Wireless Communications
Version: Author's manuscript

Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.